[tracing] Add memory usage of Android UI resources to memory-infra

cc/resources/ui_resource_bitmap.h

Index: cc/resources/ui_resource_bitmap.h
diff --git a/cc/resources/ui_resource_bitmap.h b/cc/resources/ui_resource_bitmap.h
index 23492182b35d359082445f798990b9f607780848..6f2c780fcb9081dfef259ec974b7cfaed6ea33cc 100644
--- a/cc/resources/ui_resource_bitmap.h
+++ b/cc/resources/ui_resource_bitmap.h
@@ -51,6 +51,11 @@ class CC_EXPORT UIResourceBitmap {
   UIResourceBitmap(const UIResourceBitmap& other);
   ~UIResourceBitmap();
 
+  // Returns the memory usage of the bitmap.
+  size_t GetAllocatedSizeInBytes() const {
+    return pixel_ref_ ? pixel_ref_->rowBytes() * size_.height() : 0;

[ericrk, 2016/10/14 00:07:38]

I think this is fine - in some other places we use something like:

pixel_ref_->info().getSafeSize(pixel_ref_->rowBytes());

But I don't think it matters here.

[David Trainor- moved to gerrit, 2016/10/14 01:35:31]

Ah yeah sorry I didn't realize the other method wasn't exposed.  Either of these
are probably good enough :).

[ssid, 2016/10/14 01:38:22]

Okay keeping it as is. I will ping Skia owners to expose a method. If it's done
I will fix this.
Thanks.

+  }
+
  private:
   friend class AutoLockUIResourceBitmap;